Basics

Description

Also known as “erythermalgia” and “Mitchell disease,” erythromelalgia (EM) is a clinical syndrome best described as chronic in nature that entails the hallmark symptoms of pain, erythema, and increased temperature of the extremities.

Symptoms affect the feet more commonly than the hands and have also been reported to affect the face and ears in rare occurrences.

Thought to be either a microvascular syndrome, a neurologic syndrome, or both

There are two major subtypes of the syndrome: primary and secondary.

Primary EM can further be divided into hereditary and idiopathic subsets. Secondary EM is associated with myeloproliferative disorders, essential thrombocythemia and polycythemia vera, certain medications, rheumatologic diseases, neuropathies, and infections.

Epidemiology

Primary hereditary EM is most common in patients <30 years of age (median age is 10 years) with a male-to-female ratio of 1:2.5 (1).

Secondary EM most commonly occurs in the 5th and 6th decades (median age of 61) and a 3:1 ratio of females to males (2).

IncidenceEstimates range from 0.4 to 15.0/100,000.

Etiology and Pathophysiology

Primary EM has two subcategories: idiopathic and inherited.

Secondary EM is acquired and associated with systemic diseases or other external causes.

Two major etiologic theories, vascular and neurologic, which may not be mutually exclusive:

Basics

Description

Also known as “erythermalgia” and “Mitchell disease,” erythromelalgia (EM) is a clinical syndrome best described as chronic in nature that entails the hallmark symptoms of pain, erythema, and increased temperature of the extremities.

Symptoms affect the feet more commonly than the hands and have also been reported to affect the face and ears in rare occurrences.

Thought to be either a microvascular syndrome, a neurologic syndrome, or both

There are two major subtypes of the syndrome: primary and secondary.

Primary EM can further be divided into hereditary and idiopathic subsets. Secondary EM is associated with myeloproliferative disorders, essential thrombocythemia and polycythemia vera, certain medications, rheumatologic diseases, neuropathies, and infections.

Epidemiology

Primary hereditary EM is most common in patients <30 years of age (median age is 10 years) with a male-to-female ratio of 1:2.5 (1).

Secondary EM most commonly occurs in the 5th and 6th decades (median age of 61) and a 3:1 ratio of females to males (2).

IncidenceEstimates range from 0.4 to 15.0/100,000.

Etiology and Pathophysiology

Primary EM has two subcategories: idiopathic and inherited.

Secondary EM is acquired and associated with systemic diseases or other external causes.

Two major etiologic theories, vascular and neurologic, which may not be mutually exclusive: